I think he meant specifically cases of sun under the horizon. In this case, I am afraid, Corona sky doesn't support below the horizon sky model. Although, if you use 3ds Max 2017, Autodesk has implemented universal daylight system based on old CIE model, which supports night time. And it works with Corona.

Thanks Ondra, I had no idea the sky changed in conjunction with CoronaSun lol. But some below the horizon setups like Raw alludes to would be nice, we haven't moved to 2017 yet, so I guess I'll have to fake it by eye.

we will do the below horizon thing when there is a paper on how to simulate it. I know there were tries to do it, but it is actually much more complex to properly simulate than above the horizon thing (because light has to bounce much more - night sky is "indirect lighting", day sky is "direct lighting"